/Engine/Source/Runtime/RHICore/Public/RHICoreTransientResourceAllocator.h
Allocates a buffer on a heap at a specific offset, returning a cached RHI transient buffer pointer, or null if the allocation failed. BufferSize and BufferAlignment are platform specific and must be derived from the buffer create info and passed in, along with a platform-specific buffer creation function if no cached resource if found.
[FRHITransientBuffer](API\Runtime\RHI\FRHITransientBuffer) * CreateBufferInternal ( const [FRHIBufferCreateInfo](API\Runtime\RHI\FRHIBufferCreateInfo) & CreateInfo, const TCHAR * DebugName, uint32 PassIndex, uint32 BufferSize, uint32 BufferAlignment, [FRHITransientHeap::FCreateBufferFunction](API\Runtime\RHICore\FRHITransientHeap\FCreateBufferFunction) CreateBufferFunction )